Combined street-car pneumatic door device and brake-release mechanism.



Patented Apr. 12,1910.

e bs? o L i H. RWNTREE dz G. M. SPENCER. ooMBINED STREET UAE PNEUMATIUDoon DEVICE AND BRAKE RELEASE MEGEANISM.

` PPLITIN FILED JAH. 18, 1909. 954,592.

ILLINOIS, AND GEORGE M. SPENCER, OF ST. LOUIS,

HAROLD ROWNTREE, F CHICAGO,

MISSOURI, ASSIGNORS TO BURDETT-ROWNTREE CORPORATION 0F ILLINOIS.

MANUFACTURING COMPANY, A

COMBINED STREET-CAR PNEUMATIC DOOR DEVICE AND BRAKE-RELEASE MECHANISM.

Specification of Letters Patent.

Patented Apr. 172,` 1910.

Application ledilanuary 18, 1909. Serial No. 472,951.

To all whom it may concern: y

Be it known that we, HAROLD ROWNTREE, of Chicago, count f of Cook, Stateof Illinois, and GEORGE SPENCER, of St. Louis, State of Missouri, bothcitizens of the United States, have made a certain new and usefulInvention in Combined StreetCar Pneumatic Door Device and Brake-BelegeMechanism, of which the following isa. specification. y

This invention relates to combined street car pneumatic door operatingand brake release devices.

The object of the invention is to provide means for collecting andsaving the waste or exhaust pressure, or a portion thereof, frompneumatic brake mechanism, such as is employed on street or otherrailway cars, and utilizing such waste or exhaust pressure to operate,or to control the operation of auxill s ,iary devices such as doors,steps or the like.

f The invention consists substantially in the construction, combination,location and 1e lative arrangement of parts,- all as will be more fullyhereinafter set forth, as shown V.in the accompanying drawing, andfinally pointed out in the appended claims.

In the dravvinY Figure 1 is a diagrammatic view in pan of a portion of acar 'showing the application of 'our invention for utilizing the wasteor exhaust pressure from the brake mechanism for the operation ofauxiliary devices such as doors, stepsor the like. F ig. 2 is adiagrammatic view showing a form of auxiliary device operating mechanismadapted for use in connection with our invention. Fig. 3 is a brokendetail sectional view of an automatic regulating device employed inconnection With our invention. Fi a form of controlling valve for use inconnection with our invention.

The same part is designated by the saine reference sign wherever itoccurs throughout4 the several views.

In Patent No. 877,959, granted Feb. 4, 1908, to George M. Spencer, isshown described and claimed a construction and arrangement of apparatusfor collectin and pressure from pneumatically operated brake mechamsm oncars,

. 4 is a View illustrating savlng a portion of the Waste or ex sust forreuse in the pump employed to secure the desired compression of thepressure medium, thereby enabling the pump to be maintained under adesirable load in starting up. The present invention relates to the samegeneral character of apparatus but, more particularly, to means forutilizing the conserved Waste or exhaust pressure medium for the purposeof operating auxiliary devices employed on the car, such, for instance,as doors, steps or the like.

In the drawing reference .sign 5, designates the air` compressor orpump; 6, the higher pressure tank into which the compressor or pumpdelivers; 7, an auxiliary or low pressure tank; 8 the brake cylinder;and 9, a controller for controlling the cornmunications between thetanks 6 and 7, and the brake cylinder 8.

The parts so far described may be of the usual construction andarrangement, or, as shown and described in the Spencer patent NbS-TZ-Qtlabove referred to, and the Operation there/ot2 will be readilyunderstood. The pump 5 delivers the operatingpressure medium into thehigh pressure tank (3. By suitably manipulating the controller 9, thepressure medium is supplied from the high ressure tank 6; to the brakecylinder 8, to effect the desired application of the brakes. By anotheror a further manipulation of the controller 9, the pressure medium isexhausted from the brake cylinder in order to release the brakemechanism. Instead of exhausting from the brake cylinder directly intothe atmosphere, where y the pressure of the exhaust is lost and wasted,We arrange for such exhaust to be e'ected into the auxiliary or lowpressure tank 7, until the brake cylinder and auxiliary tank pressuresare cqualized, and, thereafter, if necessary or required, the furtherexhaust from the brake cylinder to eect a complete release, may be madedirectly` into the atmosphere or otherwise, as may be desired. A. checkvalve 10, may serve to prevent the pressure in the anxiliary or lowressure tank from escaping back towards he controller 9, or the brakecylinder.

- The arrangement of the controller 9, is indicated in Fig. 4, andisxsuch that when the placed in l the j position.

,handle thereof is shown the high ressure tank is placed incommunication t rough pipe 21, with the brake cylinder to effect theapplication of the brakes, as above indicated. If the controller handleis moved slightly from this position in the direction indicated by thearrow, the brake cylinder will be shut olf from the high pressure tank,leaving the brakes applied. This is known as the lap position of thecontroller. A. further movement of the controller handle will serve toopen the brake cylinder to the low ressure tank through pipe 12, and thecontro ler will then be in what is known as the partial exhaustposition, that is, the brakes will be partially relieved. Furthermovement of the controller will open the brake cylinder to theatmosphere through the pipe 22 or otherwise.

In the o eration of brake mechanism it is always esirable to release thepressure medium more or less gradually as the car slows down, for, ifthe brakes are left fully applied until the car is nally stopped therewould be an objectionable jerky stop of the car, and if the brakes arerelieved too soon there would be a failure to stop at the right point.In order to obtain the preliminary or partial exhaust it is customary toemploy a comparatively small partial exhaust opening, or if only asingle exhaust opening is used it is o ened only slightly in partial eX-haust position, so that the air from the brake cylinder will not esca eto the atmosphere too ra idly, but when tlie controller is moved to fulexhaust position a free exhaust is obtained. In accordance with ourinvention we separate the preliminary or partial exhaust from the fullor free exhaust and pipe the connection from the partial exhaust to thelow pressure tank. Therefore, each time the handle of the controller 9,is placed in partial exhaust the air brake cylin er equalizes or tendsto equalize into the low pressure tank 7, with the result that anydesired pressure may be maintained in the low pressure tank, the checkvalve l0, preventing the pressure from escaping from the low pressuretank when the controller is moved to full exhaust position.

It is important that the pressure in the low pressure tank be preventedfrom falling below a predetermined point through use of the ressuretherefrom for the operation of auxi ia devices, such as doors, steps orthe like. IIt is equally important that the pressure in the low pressuretank be prevented rom exceeding a predetermined maximum. For, if throughfailure to use the pressure in the low pressure tank for the operationof auxiliary devices, o r for other purposes, and the brake mechanism ismeanwhile applied and released several tim, the pressure in the low4pressure tank osition the pressure in i wouldbuild up and increase untilthere is a failure to secure the desired preliminary or partial releaseof the brake mechanism when the controller handle is moved to partialrelease position, silice the low pressure tank, and the brake cylinderpressures will have been brought to equality by the accumulation of thepressure in said tank. On the other hand, if the pressure in the lowpressure tank is permitted to fall below a de sii-able point there maynot be suiiicient pressure therein to effect the operation of theauxiliary devices. In order to avoid these and other dilliculties wepropose, in accordance with the principles of our invention, to employ apressure regulator having such relation and arrangement as to maintainsubstantially anuniform pressure in the low pressure tank. This pressureregulator is inter osed between the pipes 11, 12, respective ydelivering from the hi h pressure tank 6 to the controller 9, an fromthe controller to the low pressure tank 7, and consists of a cylinder13, having a piston 14, therein, exposed on one side to the pressuremedium and on the other side to the atmosphere and to the tension of acomprsion s nng 15. A valve 1G, connected to the ro 17 of the piston,controls two orts, one delivering by pipe 18, or otherwise to theatmosphere, and the other communicating by pipe 19, or otherwise, withthe high pressure tank 6. A pipe 20, communicates etween the cylinder13, on the pressure side of piston 14, and the low pressure tank. Thetension of spring 15 is regulated to the required point to enablesubstantially uniform pressure to be maintained in the low pressuretank. In the ositioii shown in Fig. 3, both ports control ed by valve16, are closed while there is a free communication between the regulatorcylinder and the low ressure tank. If now, the ressure in the ow preuretank should all below the point as predetermined b the tension of spring15, said spring wil actuatethe piston 14 aiid through it the valve 16,in a direction to open the connection 19to the regulator cylinderthereby admitting pressure from the high ressure tank to the lowpressure tank until the pressure in the latter rises sufficiently toovercome the tension of spring 15, and again cause valve 16, to shutoil' the connection 19, from the high pressure tank. On the other hand,if the pressure in the low pressure tank builds up to a degree above thepredetermined maximum the tension of sprin 15, will be overcome and thepiston 14, w1 l move in a direction to cause valve 1G, to open theexhaust connection 18, thereby causing the ressure in the low pressuretank to again fnl Thus it will be seen that We secure automatically amost eflicient regulation and control of the pressure in the lowpressure tank.

lll

From the low pressure tank 5, in which Waste or exhaust ressure from thebrake cylinder is collected) and stored, the pressure medium is drawnfor use in operating the auxiliary devices. In the particular embodimentof our invention which We have selected for the purposes ofillustration, We have shown an arrangement for effecting the operationof the car door, but of course it is to be understood that ourinvention, as d efined in the claims, is not to be confined or limitedwith respect to the particular form of auxiliary devices to be operated,as it is obvious that other devices besides doors, such for instance, assteps, bells, whistles, sanding mechanism and the like may be operatedor controlled with equal facility by the stored up or conserved waste orexhaust pressure from the brake cylinder.

In the form shown a pipe 23, delivers from the low pressure tank 7, to avalve casing 24, in which a suitable valve controls the supply andexhaust of the pressure medium to and from the power cylinder 25, foroperating suitable mechanism, indicated at 26, havin connection withVthe door 27, for contro ling the movements of the latter. The suppl andexhaust of the medium to and from t 1e power cylinder 25, may becontrolled from any convenient point and through any convenient valveoperation conneetions. XVe have shown a valve control. handle 28, andintermediate connections 29, for this purpose.

In ending applications for patents ot' Harol Rowntree, Serial No.393,911, tiled Sept. 21, 1907, and of Paris R. Forman .Serial No.393,908, filed Sept. 21, 1907, and in Patent No. 870,051, granted Nov.5, 190.7, to Rowntree, are shown various forms and constructions ofauxiliary devices such as door and ste operating means which can beemployed in connection with our piesent invention, and thereforespecilic and detailed description of such devices herein is unnecessary.

From the foregoing description it will be seen thatl we rovide meanswhich are simple and'e'ieient or operating the doors, or other auxiliarydevices from the exhaust or Waste from the brake mechanism, and hencewithout requiring any special compressor mechanism for the pressuremedium, and Without imposing any extra duty on the com presser er pumpemployed in connection with the brake mechanism. While the amount ofcompressed air required for operating the doors, steps or the like, ofcars is not great, and While when the equipment is new the compressorfor the brake mechanism is usually amply able to supply the requiredpressure for operating the brakes, as Well as auxiliary devices, yet,owing to the natural Wear and tear incident to continued service use ofthe apparatus, the capacity l said means exhausts,

of the `compressor in relation to the brake pressure required, islessened until a point is reached Where the pressure supplied therefromis not more than `that required to properly operate the brakes, and eventhe slight additional duty imposed thereon when pressure medium is drawndirectly therefrom for operatin the doors or other auxiliary devices issuicicnt to overtax the compressor with the result that neither thebrakes nor the auxiliary devices are properly or etticiently operated.It will be observed that in our invention we overcome this diiiiculty byutilizing the waste or exhaust from the brake cylinder. VIt will also beseen that our invention may be readily applied to cars already in useand equipped With air brake mechanism, thereby enabling such cars to bereadily supplied with pneumatic door or step operating mechanism withoutimposing any extra duty on the air brake compressor.

Having now set forth the object and nature of our invention, and aconstruction and arrangement embodying the principles thereof, andhaving described such construction its purposes, tunction and mode ot'operation, What we claim as new and useful, and of our own invention,and desire to seby Letters Patent is l. In a car, the combination withpressure operated brake mechanism, of a door or other auxiliary device,actuating means connected thereto, and means for utilizing the exhaustfrom the brake mechanism for operating the actuating means of said dooror other auxiliary device.

In a car, the combination with pressure operated brake mechanism, ofauxiliary n'iovable devices, actuating means therefor, means for storinga portion of the exhaustv from the brake mechanism, and means forutilizing the stored exhaust pressure to operate said actuating means.

3. In a car, the combination with pressure operated brake mechanism, andmeans for etl'ecting a partial exhaust of the pressure medium togradually release the brake mechanism, of means for storing up thepartial exhaust from the brake mechanism, auxiliary movable pressureoperated de vices, and means for utilizing the stored 'up partialexhaust from the brake mechanism for moving said auxiliary devices.

4. In a car, the combination with an air brake mechanism means forpartially exhausting the operating vmedium therefrom in advance of thefull exhaust, and means for storing up the partial exhaust, of a door,and means for utilizing the stored up partial exhaust for operating thedoor.

5. In a car, the combination of a high pressure tank, a compressordelivering thereto, means operated by the pressure from said tank, a lowpressure tank into which and auxiliary movable devices operated bypressure from said low pressure tank.

6. In a car, the combination of a highl pressure tank and a low pressuretank, means operated by pressure from the high pressure tank andexhausting into the low pressure tank, a check valve for preventing thereturn of such exhaust pressure from the low pressure tank, andauxiliary movable means having actuating devices operated by pressurefrom the low pressure tank.

7. In a car, the combination of a high pressure tank, a low pressuretank, means operated by pressure from the high pressure tank andexhausting into the low pressure tank, auxiliary devices operated bypressure from the low pressure tank, apressurf` regulator communicatingrespectively with said tanks and the atmosphere and including anautomatically operated valve for controlling said communications.

8. In a car, a pump, a tank to Which the pump delivers, a brakemechanism operated from said tank, a low pressure tank into which thebrake mechanism exhausts, a power cylinder supplied with operatingmedium from said low pressure tank, a door, and mechanism operated bysaid power mechanism for moving said door.

S). In a,V car, a high pressure tank, a low pressure tank and a brakecylinder, a controller for controlling the connections between saidtanks and cylinder and operating to supply pressure medium from the highpressure tank to the brake cylinder, and to supply the exhaust from saidcylinder to the low pressure tank, auxiliary movable devices, pressureactuated means for operating said devices, and means for supplyingpressure from said low pressure tank to said pressure actuated means.

10. In a car, the combination with pressure operated brake mechanism, ofressure operated auxiliary detices, means or storing a portion of theexhaust from the brake mechanism, and means for maintaining said storedexhaust to operate the auxiliary device.

11. In a car, `the combination with pressure operated brake mechanism,and means for eli'ccting a partial exhaust of the pres sure medium inadvance of the full exhaust to gradually release the brake mechanism, ofmeans for storing up the partial exhaust from the brake mechanism, meansfor preventing said stored up partial exhaust pressure from exceeding apredetermined maximum, auxiliary pressure operated devices, and meansfor utilizing the stored up partial exhaust pressure for operating saidauxiliary devices.

12. In a car, the combination with an air brake mechanism, means forpartially exhausting the operatin medium therefrom in advance of the fulexhaust, means for storing up the partial exhaust pressure, and meansfor preventing the stored up partial exhaust pressure from falling belowa predetermined minimum pressure, of a door, and means for utilizing thestored up partial cxhaust pressure for operating' the door.

13. In a car, the combination ot a high pressure tank,'a compressordelivering their to, means operated by the pressure from said tank, alow pressure tank into which said means exhausts, means for maintainingsubstantially uniform pressure in the low pressure tank, and auxiliarydevices operated by pressure from said loW pressure tank.

In testimony whereof We have hereunto set our hands in the presence ofthe subscribing Witnesses, this 11th day of Jannary A. D., 1909.

HAROLD ROWNTREE.

GEORGE M. SPENCER Witnesses:

LEMUEL M. SHIELDS, ADELINE F. BISHOP.

